Exploring Phoneme-Level Speech Representations for End-to-End Speech Translation
Elizabeth Salesky, Matthias Sperber, Alan W. Black · 2019
Previous work on end-to-end translation from speech has primarily used frame-level features as speech representations, which creates longer, sparser sequences than text.We show that a naïve method to create compressed phoneme-like speech representations is far more effective and efficient for translation than traditional frame-level speech features.Specifically, we generate phoneme labels for speech frames and average consecutive frames with the same label to create shorter, higher-level source sequences for translation.We see improvements of up to 5 BLEU on both our high and low resource language pairs, with a reduction in training time of 60%.Our improvements hold across multiple data sizes and two language pairs.